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Poster: Administrator, Curator, or StaffNemo_bis Date: Jan 6, 2013 1:02am
Forum: opensource Subject: Re: Derivation failed from PDF: ppmtobmp failed with exit code: 1

So, thanks to the very helpful IA staff I've found out that it was enough to force the ppi value: my fault that I used the wrong field, you have to use "fixed-ppi" (example). We've indeed set it to 75; in a case I further reduced it to 36, even.

The problem which causes that huge size ("median page size: 63.014 x 83.611") is that those PDFs use points instead of pixels, and those are not recognized well. ProcessJP2 usually takes only a few minutes, here it fails because otherwise it would produce image files dozens of times bigger than they should be.
I guess one should avoid uploading such PDFs, or if they're taken elsewhere a "fixed-ppi" value should be set from start; in most cases, including the one mentioned above, 300 is low enough.
pdfinfo shows the pts/points in "Page size", like this:

Creator: pdftk 1.40 - www.pdftk.com
Producer: itext-paulo-155 (itextpdf.sf.net-lowagie.com)
CreationDate: Tue Nov 25 09:54:20 2008
ModDate: Tue Nov 25 09:54:20 2008
Tagged: no
Pages: 84
Encrypted: no
Page size: 4537 x 6020 pts
File size: 22693186 bytes
Optimized: no
PDF version: 1.4

I also found some with "GPL Ghostscript 906 (ps2write)" and a commercial "professional" product I can't remember, but it doesn't to be a specific producer's "fault".